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Heating and Cooling› Thermostats, Housings and Fillers

Mishimoto

Mishimoto High-Pressure 1.3 Bar Radiator Cap - Small - One-Way

$29.00 $25.95 Save $3.05

SKU: M00C MMRC-13-ONWY

In Stock
In Stock
Ships by Oct 19
Free Shipping over $200
$100 Minimum Order
30 Days Return
INSTALL DIFFICULTY
DIY PRO SHOP

Beginner — under 30 min

Overview

The Mishimoto MMRC-13-ONWY is a high-pressure radiator cap designed for Subaru vehicles. It features one-way functionality, matching the OEM design for a guaranteed perfect fit and appropriate system operation. This 1.3 bar (19 psi) cap raises the boiling point of engine coolant, contributing to a safer and more efficient cooling system.
Show original supplier description

Part #: MMRC-13-ONWY

Maximize your Subaru's performance with the Mishimoto High-Pressure 1.3 Bar Radiator Cap. When pushing your vehicle under demanding driving conditions, the cooling system becomes highly pressurized, often exceeding the limits of stock caps. This leads to coolant loss into the overflow reservoir, compromising performance. Engineered specifically for Subaru vehicles, with one-way functionality matching the OEM radiator cap design, guaranteeing appropriate operation of your Subaru's cooling system. The Mishimoto cap maintains optimal coolant flow by withstanding higher pressures. Its direct-fit design ensures easy installation, and the unique, non-directional sticker means it's always facing the right way. Upgrade your Subaru's cooling system and experience the difference in performance with the Mishimoto High-Pressure Radiator Cap.

Vehicle Symptoms
  • coolant boiling out of overflow tank
  • coolant loss after hard driving
  • engine temperature creeping up under load
  • hissing sound from radiator cap area
  • coolant overflow after engine shutdown
Diagnostic Codes
  • P0217 – Engine Coolant Overtemperature Condition
Relevant Conversations
  • Subaru overheating after hard driving coolant loss
  • coolant boiling out of overflow bottle when hot
  • P0217 coolant overtemperature code Subaru
  • 1.3 bar radiator cap vs stock Subaru worth it?
  • Mishimoto MMRC-13-ONWY radiator cap install
  • radiator cap not holding pressure symptoms
  • Subaru track day coolant overflow fix
  • high pressure radiator cap for Subaru WRX
  • Mishimoto radiator cap vs OEM cap pressure
  • coolant boiling in reservoir after shutdown

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

Fitment

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Specifications

BrandMishimoto
Part NumberM00C MMRC-13-ONWY

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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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